黄土丘陵区弃耕地恢复过程中土壤与植物恢复特征

发布时间：2018-06-05 17:38

本文选题：黄土丘陵区 + 恢复年限　；参考：《草业科学》2016年03期

【摘要】：采用对比分析以及空间代替时间的方法,根据黄土丘陵区5个恢复年限(0-5、6-10、11-15、16-20和21-25年)弃耕地的调查数据,研究其在植被恢复过程中随着弃耕年限的增加植物群落生物量及其土壤养分的变化特征。结果表明,在5个恢复阶段内黄土丘陵区主要的优势物种依次为赖草(Leymus scalinus)、猪毛蒿(Artemisia scoparia)、达乌里胡枝子(Lespedeza davurica)、长芒草(Stipa bungeana)、白羊草(Bothriochloa ischaemun)。期间,Simpson多样性指数(D)、Shannon-Wiener多样性指数(H)、Pielou均匀度指数(Jsw)、Margalef丰富度指数(Dma)总体上均呈先增大后减小的趋势,其植被覆盖度呈逐渐增加的趋势,这表明黄土丘陵区的植被生物量在自然和人工恢复方式下可以逐渐增加。随着植被恢复年限的增加,黄土丘陵区地上生物量总体上呈现先减少后增加的趋势。土壤养分含量随土层深度(0-20、20-40、40-60cm)的增加而下降,随植被恢复年限的增加土壤有机质、全N和速效K含量呈先减少后增大的趋势,土壤全P含量呈先增大后减小的趋势。植被恢复过程中,21-25年的土壤有机质和全N含量达到峰值,16-20年的土壤全P含量达到峰值,这表明在植被恢复过程中黄土丘陵区土壤养分含量能够得到一定改善,但改善速度缓慢。
[Abstract]:Using the method of comparative analysis and space substitute time, according to the survey data of abandoned farmland in the loess hilly area from 0-56-106-1011-15 / 16-20 and 21-25 years, The variation characteristics of plant community biomass and soil nutrient were studied with the increase of abandoned tillage years during the process of vegetation restoration. The results showed that the dominant species in the loess hilly region were Leymus scalinusus, Artemisia scoparia, Lespedeza davuricaer, Stipa bunanagege and Bothriochloa chaemunus. During the period, the diversity index of Simpson, Shannon-Wiener diversity index, Pielou evenness index, and the abundance index of Margalef of Jswgna showed a trend of increasing first and then decreasing, and the vegetation coverage showed a trend of increasing gradually. This indicates that the vegetation biomass in loess hilly region can be gradually increased under natural and artificial restoration mode. With the increase of vegetation restoration years, the aboveground biomass in loess hilly region decreased first and then increased. Soil nutrient content decreased with the increase of soil depth (0-20 ~ 20 ~ 40 ~ 40 ~ 60 cm). With the increase of vegetation restoration years, total N and available K content decreased first and then increased, and soil total P content increased first and then decreased. During vegetation restoration, soil organic matter and total N content reached the peak in 21-25 years and reached the peak value in 16-20 years, which indicated that the soil nutrient content in loess hilly region could be improved in the process of vegetation restoration, but the improvement rate was slow.
【作者单位】：西北农林科技大学资源环境学院;西北农林科技大学水土保持研究所;中国科学院水利部水土保持研究所;
【基金】：国家自然科学基金项目(41271043、31370455) 中国科学院知识创新工程“百人计划”项目
【分类号】：S154.4

【参考文献】